Conventionally, a bearing device having a plurality of partial pads (that is, tilting pad bearing, and journal bearing) is known as a bearing device applied to support a rotor of a large rotary machine such as a steam turbine, gas turbine, a nuclear power turbine and the like.
As shown in FIG. 4, in the bearing device 101, a bearing body 103 is supported by a support ring 102, and a rotor 4 of a rotary machine is supported by a plurality of bearing pads 109 interspatially positioned along a circumferential direction of the rotor 4 so as to be swingable.
A key member 110 for restricting movement of the bearing body 103 in the radial direction is inserted between the support ring 102 and a carrier ring 108 which forms an outer circumference of the bearing body 103.
For example, the centering of the rotor 4 in the steps of installation, disassembly, and reassembly of the steam turbine, and the readjustment to fix a misalignment of the axis of the rotor 4 due to an external factor such as ground subsidence are performed by changing the thickness of the key member 110 in the rotor radial direction.
Specifically, the positional adjustment of the bearing body 103 is performed by ejecting the bearing body 103 temporarily from the bearing device 101 and adjusting the liner member interposed between the key member 110 and the carrier ring 108. This adjustment operation is performed in an installed state of the rotor 4, and thus, the operation is difficult because the bearing body 103 needs to be elevated while rotating around the rotor 4. In addition, it is necessary to perform a bedding-in of a contacting surface between the support ring 102 and the key members 110 for each adjustment in order to avoid a so-called partial contact where the support ring 102 and the key member 110 are locally in contact with each other.
Patent Document 1 discloses a bearing device provided with a key member configured to be freely insertible and removable in the rotor axial direction in order to facilitate the centering of the rotor 4 (adjusting the alignment of the rotor axis).